Bioequivalence and Bioavailability Forum

Dear Chirag,

No regulatory reference that I know of. This depends on the bench-top stability you have demonstrated during method validation. 30 minutes would be much, much too long for some nitrate derivates (e.g. trinitrin - glyceryl trinitrate). Other compounds can sit for hours on the bench without any damage.

Regards
Ohlbe

Dear Chirag!

❝ The concept we follow is after collection of blood within 30 minutes separation and storage should be done,…

Some remarks additionally to Ohlbe’s post…
It’s quite difficult to validate the degradation process. It would consist of spiking whole blood at 37 ℃ and carrying it through different conditions to the frozen plasma.
Most difficulties arise from:

• spiking low volumes precisely
  
• allowing some time for equalization (protein binding!)

Many people just skip this step in validation (to my knowledge it’s not covered in a guideline) assuming similar degradation for test/reference in BE.
To be on the safe side you may transfer your samples immediately after collection to a thermostated water bath (if you don’t have one, a water tank with ice-cubes or a beaker filled with crushed ice also does the job) until centrifugation. According to the Arrhenius-equation this procedure is expected to bring down the degradation to about 20%.

BTW, how do you actually keep the interval from collection to storage at ≤30 minutes? The run-time of the centrifuge is probably 15-20 minutes and especially in the early collection periods (let’s say the first 2 hours) you must perform the separation in some kind of batch mode – unless you have an entire battery of cooled centrifuges in your department…